Inflatable building structures, including various dome-shaped inflatable building structures are known in the prior art. For example:
U.S. Pat. No. 4,164,829 for an INFLATABLE STRUCTURE describes an inflatable dome-shaped structure which is held up by internal air pressure. This structure depends on internal air pressure for support, therefore it cannot be ventilated unless it has a constant supply of pressurized air, which would make it unsuitable for use as a greenhouse for plants.
U.S. Pat. No. 4,876,829 for an INFLATABLE TENT STRUCTURE describes a dome-shaped tent having an external supporting framework of elongated inflatable tubes which interconnect at the apex of the tent. U.S. Pat. No. 5,007,212 for an INFLATABLE SHELTER describes a similar dome-shaped tent having a ring-shaped inflatable, tubular base and inflatable, tubular support ribs converging near the apex of the tent to hold up the tent walls. The inflatable tent structures described in these two patents are single-walled structures which would not provide very much insulative protection for use as a greenhouse for plants. Because these structures are intended for use as camping tents, the walls of the structures are in large part opaque, which also makes them unsuitable for use as a greenhouse for plants.
U.S. Pat. No. 4,807,405 for a GEODESIC INFLATABLE STRUCTURE AND METHODS OF UTILIZING SAME describes a dome-shaped structure having a lattice-like support framework of inflatable tubular ribs and triangular inflatable panels between the ribs. This patent describes a very complex structure, requiring many, many linear welding seals to form the lattice-like support framework and the triangular inflatable panels. The complexity of this structure would undoubtedly make it expensive to produce.
U.S. Pat. No. 4,384,435 for an INFLATABLE TENT describes an inflatable hemispherical tent having multiple compartments in the shape of orange sections. The inflatable compartments are interconnected at the top of the tent by a manifold. The construction of the inflatable compartments in this structure requires several long, curved welding seals between the marginal edges of each section and between the edges of each section and the internal walls that separate the compartments. This is a complex and potentially expensive manufacturing process.
U.S. Pat. No. 4,583,330 for a MODULAR INFLATABLE DOME STRUCTURE describes a dome-shaped structure having a modular support framework formed of uniform length inflatable tubes which are joined together by uniform Y-joints. The inflatable support framework hardens by vulcanization after inflation to form a permanent structure. The permanency of the vulcanized framework would make this structure unsuitable for use as a temporary greenhouse for plants.
In addition, inflatable greenhouses are known in the prior art. For example:
U.S. Pat. No. 4,027,437 for an INFLATABLE BUILDING describes a rectangular inflatable structure which is adapted for use as a greenhouse for plants. The inflatable structure is not self-supporting, but it requires a separate rigid framework for holding up the inflatable tubes which make up the walls of the structure.
U.S. Pat. No. 5,433,030 for a PLANT PROTECTOR describes a cylindrical inflatable greenhouse for plants with a doorway through the cylindrical wall. The walls of the inflatable cylindrical structure are constructed with multiple interconnected horizontal rings formed by long welded seams which encircle the structure. An opaque lower ring is separately inflatable with water to act as a ballast for the structure. The long multiple welded seams between the rings would add to the manufacturing cost of the structure. In addition, the inflatable structure is not totally self-supporting. The doorway of the structure must be reinforced with a rigid material, such as wood, to prevent the structure from deforming.
None of the prior art inflatable shelters or buildings provides a totally self-supporting dome-shaped inflatable structure, which does not require any rigid support members, is inexpensive to manufacture, and provides sufficient light transmission, thermal protection, ventilation and interior access to make it suitable for use as a temporary greenhouse structure.